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Phosphorothioic acid, O,O-dimethyl O-(p-nitrophenyl) ester

RTECS #
TG0175000
CAS #
298-00-0; 37359-35-6
See: NMAM or OSHA Methods
Updated
December 2017
Molecular Weight
263.22
Molecular Formula
C8H10NO5PS
Synonyms
8056HC
Azofos
Azophos
BAY 11405
BAY E-601
Bladan-M
Cekumethion
Dalf
Demethylfenitrothion
Devithion
Dimethyl 4-nitrophenyl phosphorothionate
Dimethyl parathion
Dimethyl p-nitrophenyl monothiophosphate
Dimethyl p-nitrophenyl thiophosphate
Dimethyl-p-nitrophenyl thionphosphate
Drexel methyl parathion 4E
ENT 17,292
Folidol M
Folidol-80
Fosferno M 50
Kilex parathion
Mepaton
Meptox
Metacid
Metacid 50
Metafos
Metaphos
Methyl fosferno
Methyl niran
Methyl parathion
Methyl parathion (ACGIH)
Methyl-E 605
Metilparation (Hungarian)
Metron (pesticide)
Metyloparation (Polish)
Metylparation (Czech)
M-Parathion
NCI-C02971
Nitrox
Nitrox 80
O,O-Dimethyl O-(p-nitrophenyl) phosphorothioate
O,O-Dimethyl O-(p-nitrophenyl) thionophosphate
O,O-Dimethyl O-4-nitrophenyl phosphorothioate
O,O-Dimethyl O-p-nitrophenyl thiophosphate
O,O-Dimethyl-O-(4-nitro-fenyl)-monothiofosfaat (Dutch)
O,O-Dimethyl-O-(4-nitrophenyl) phosphorothioate
O,O-Dimethyl-O-(4-nitro-phenyl)-monothiophosphat (German)
O,O-Dimethyl-O-(4-nitrophenyl)-thionophosphat (German)
O,O-Dimethyl-O-(p-nitrophenyl)-thionophosphat (German)
O,O-Dimethyl-O-p-nitrofenylester kyseliny thiofosforecne (Czech)
O,O-Dimethyl-O-p-nitrofenylthiofosfat (Czech)
O,O-Dimetil-O-(4-nitro-fenil)-monotiofosfato (Italian)
Oleovofotox
Parapest M-50
Parataf
Parathion methyl
Parathion-metile (Italian)
Penncap-M
Phenol, p-nitro-, O-ester with O,O-dimethylphosphorothioate
Phosphorothioic acid, O,O-dimethyl O-(4-nitrophenyl) ester
p-Nitrophenyldimethylthionophosphate
Quinophos
RCRA waste number P071
Sinafid M-48
Tekwaisa
Thiophenit
Thiophosphate de O,O-dimethyle et de O-(4-nitrophenyle) (French)
Thylpar M-50
Vofatox
Wofatox
Yphos

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
Cytogenetic Analysisintraperitoneal/rat3 mg/kgMUREAV 321,103,1994
Cytogenetic Analysisoral/mouse10 mg/kgSOGEBZ 11,1534,1975
Cytogenetic Analysissperm/human300 µmol/L/1HREPTED 25,455,2008
DNA Damagesperm/human3.435 mmol/L/1HREPTED 25,455,2008
DNA Damageintraperitoneal/mouse6 mg/kgTXAPA9 216,216,2006
DNA Damageother cell types/human1 mg/L/24HEMMUEG 49,360,2008
DNA Damageother cell types/human100 mg/L/4HEMMUEG 49,360,2008
DNA Damagelymphocyte/rat0.00675 mg/L/2HMUREAV 761,10,2014
DNA Damagelymphocyte/rat0.00675 mg/L/4HMUREAV 761,10,2014
DNA Damage/Escherichia coli100 mg/LMUREAV 52,161,1978
DNA repair/Salmonella typhimurium250 µg/discJPFCD2 19,565,1984
DNA repair/Other microorganisms50 µL/plateBIZNAT 95,463,1976
Dominant Lethal Testoral/Drosophila melanogaster4500 ng/LFCTOD7 33,309,1995
gene conversion and mitotic recombination/Saccharomyes cerevisiae114 mmol/LIARCCD 10,161,1974
micronucleus testintraperitoneal/mouse1 mg/kgMUREAV 155,131,1985
micronucleus testoral/mouse9375 µg/kgMUTAEX 5,147,1990
micronucleus testintraperitoneal/rat2500 µg/kg/5D-continuousMUREAV 188,45,1987
micronucleus testother cell types/human0.1 mg/L/4HMUREAV 671,84,2009
mutation in mammalian somatic cellslymphocyte/mouse100 mg/LNTIS** PB84-138973
mutation in microorganisms/Salmonella typhimurium0.5 mmol/L/3D (+enzymatic activation step)MUREAV 536,103,2003
mutation in microorganisms/Salmonella typhimurium667 µg/plate (+enzymatic activation step)ENMUDM 5(Suppl 1),3,1983
mutation in microorganisms/Escherichia coli10 mmol/L (-enzymatic activation step)MUREAV 20,7,1973
mutation in microorganisms/Other microorganisms100 mg/L (-enzymatic activation step)CYGEDX 15(3),64,1981
mutation in microorganisms/Salmonella typhimurium0.5 mmol/L/72H (+enzymatic activation step)MUREAV 536,103,2003
sister chromatid exchangelung/hamster10 mg/LMUREAV 88,307,1981
sister chromatid exchangelymphocyte/human20 mg/LMUREAV 88,307,1981
specific locus testmultiple/Drosophila melanogaster31500 ppbARTODN 61,53,1987
specific locus testoral/Drosophila melanogaster6 µg/LFCTOD7 33,309,1995
sperm morphologyintraperitoneal/rat6 mg/kg/12D- intermittentMUREAV 588,28,2005
sperm morphologyintraperitoneal/rat18.75 mg/kg/25D- intermittentMUREAV 588,28,2005
sperm morphologyoral/mouse9375 µg/kgMUREAV 280,169,1992

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
intraperitoneal/rat 15 mg/kg (13D pregnant)Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)AEHLAU 15,609,1967
intraperitoneal/rat 45 mg/kg (15D prior to copulation)Reproductive: Maternal effects: Menstrual cycle changes or disorders

Reproductive: Effects on newborn: Live birth index (Litter size (e.g., # fetuses per litter; measured after birth)

Reproductive: Effects on newborn: Viability index (e.g., # alive at day 4 per # born alive)
IJEBA6 37,176,1999
intraperitoneal/mouse 60 mg/kg (11D pregnant)Reproductive: Effects on embryo or fetus: Fetal death

Reproductive: Specific developmental abnormalities: Craniofacial (including nose and tongue)

Reproductive: Specific developmental abnormalities: Musculoskeletal system
AEHLAU 15,609,1967
intraperitoneal/rat 12 mg/kg (12D male)Reproductive: Maternal effects: Breasts, lactation (prior to or during pregnancy)MUREAV 588,28,2005
intraperitoneal/rat 18.75 mg/kg (25D male)Reproductive: Effects on fertility: Female fertility index (e.g., # females pregnant per # sperm positive females; # females pregnant per # females mated)

Reproductive: Effects on fertility: Male fertility index (e.g., # males impregnating females per # males exposed to fertile nonpregnant females)
MUREAV 588,28,2005
intraperitoneal/rat 37.5 mg/kg (25D male)Reproductive: Effects on newborn: Viability index (e.g., # alive at day 4 per # born alive)MUREAV 588,28,2005
oral/rat 20 mg/kg (1-20D pregnant)Reproductive: Other effects on female

Reproductive: Effects on fertility: Post- implantation mortality (e.g., dead and/or resorbed implants per total number of implants)

Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)
ETPAEK 55,489,2004
oral/rat 20 mg/kg (1-20D pregnant)Reproductive: Effects on embryo or fetus: Extra embryonic structures (e.g., placenta, umbilical cord)HETOEA 27,241,2008
oral/mouse 5 mg/kg (1D prior to copulation)Reproductive: Effects on newborn: Growth statistics (e.g., reduced weight gain)TXAPA9 279,338,2014
oral/mouse 20 mg/kg (1D prior to copulation)Reproductive: Effects on newborn: Other postnatal measures or effectsTXAPA9 279,338,2014
oral/rat 900 mg/kg (30D male)Reproductive: Effects on fertility: Male fertility index (e.g., # males impregnating females per # males exposed to fertile nonpregnant females)ETOPFR 14,91,2003
oral/rat 9 mg/kg (7-15D pregnant)Reproductive: Effects on newborn: Weaning or lactation index (e.g., # alive at weaning per # alive at day 4)

Reproductive: Effects on newborn: Behavioral
JPFCD2 15,365,1980
oral/rat 15 mg/kg (6-15D pregnant)Reproductive: Effects on fertility: Post- implantation mortality (e.g., dead and/or resorbed implants per total number of implants)

Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)

Reproductive: Specific developmental abnormalities: Blood and lymphatic systems (including spleen and marrow)
JEBIDP 17,51,1996
oral/rat 600 µg/kg (5-15D pregnant)Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)AXVMAW 30,343,1976
oral/rat 2200 µg/kg (1-22D pregnant)Reproductive: Effects on newborn: Growth statistics (e.g., reduced weight gain)GISAAA 38(8),21,1973
skin/rat 10 mg/kg (18D pregnant)Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)

Reproductive: Specific developmental abnormalities: Central nervous system
JTEHD6 63,173,2001
unreported route/rat 44 mg/kg (1-22D pregnant)Reproductive: Effects on newborn: BehavioralAMSHAR 28,210,1980

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
In Vitro/Human, liver tumor Inhibitor Concentration Low: 6 µmol/L/72HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 25,2074,2011
In Vitro/Human, liver tumor Inhibitor Concentration Low: 2 µmol/L/48HIn Vitro Toxicity Studies: Other assaysTIVIEQ 25,2074,2011
In Vitro/Non-mammalian species, liver Inhibitor Concentration Low: 13 µmol/L/24HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 29,204,2015
In Vitro/Non-mammalian species, liver Inhibitor Concentration Low: 0.13 µmol/L/24HIn Vitro Toxicity Studies: Other assaysTIVIEQ 29,204,2015
inhalation/mouse lethal concentration (50 percent kill): 120 mg/m3/4HBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesteraseNTIS** PB241-840
inhalation/rat lethal concentration (50 percent kill): 34 mg/m3/4HBehavioral: Tremor

Behavioral: Muscle contraction or spasticity

Lung, Thorax, or Respiration: Dyspnea
EGESAQ 24,173,1980
intracerebral/mouse lethal dose (50 percent kill): 47 mg/kgPCBPBS 8,302,1978
intraperitoneal/mouse lethal dose (50 percent kill): 5400 µg/kgPCBPBS 8,302,1978
intraperitoneal/rat lethal dose (50 percent kill): 2800 µg/kgAPCRAW 4,117,1961
intravenous/guinea pig lethal dose (50 percent kill): 50 mg/kgBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesteraseNTIS** PB241-840
intravenous/mouse lethal dose (50 percent kill): 9800 µg/kgBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesteraseNTIS** PB241-840
intravenous/rat lethal dose (50 percent kill): 9 mg/kgNTIS** PB277-077
oral/Dog lethal dose (50 percent kill): 90 mg/kgGastrointestinal: Nausea or vomitingPESTD5 16,273,1975
oral/duck lethal dose (50 percent kill): 10 mg/kgDOEAAH 35,25,1979
oral/guinea pig lethal dose (50 percent kill): 1270 mg/kgBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesteraseNTIS** PB241-840
oral/mammal (species unspecified) lethal dose (50 percent kill): 57 mg/kgBehavioral: Tremor

Behavioral: Ataxia

Lung, Thorax, or Respiration: Dyspnea
NTIS** PB288-416
oral/man lowest published toxic dose: 0.17 gm/kgBlood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other esterases
JTCTDW 45,956,2007
oral/man lowest published lethal dose: 0.286 gm/kgBlood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other esterases
JTCTDW 45,956,2007
oral/mouse lowest published toxic dose: 5 mg/kgReproductive: Maternal effects: OogenesisTXAPA9 279,338,2014
oral/mouse lethal dose (50 percent kill): 17800 µg/kgHETOEA 11,11,1992
oral/rabbit lethal dose (50 percent kill): 420 mg/kgBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesteraseNTIS** PB241-840
oral/rat lowest published toxic dose: 0.6 mg/kgBehavioral: Tremor

Behavioral: Convulsions or effect on seizure threshold
TOSCF2 76,400,2003
oral/rat lethal dose (50 percent kill): 6 mg/kgJTCTDW 45,956,2007
oral/rat lowest published toxic dose: 1.75 mg/kgBrain and Coverings: Other degenerative changes

Blood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
TOXID9 72,309,2003
oral/wild bird lethal dose (50 percent kill): 5 mg/kgJTCEEM 6(3),175,1986
skin/duck lethal dose (50 percent kill): 54 mg/kgTXAPA9 47,451,1979
skin/mouse lethal dose (50 percent kill): 1200 mg/kgBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesteraseJTEHD6 9,491,1982
skin/rabbit lethal dose (50 percent kill): 300 mg/kgAFDOAQ 16,3,1952
skin/rat lethal dose (50 percent kill): 67 mg/kgWRPCA2 4,36,1965
skin/rat lowest published toxic dose: 10 mg/kgLung, Thorax, or Respiration: Respiratory stimulation

Blood: Changes in leukocyte (WBC) count

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
JTEHD6 63,173,2001
subcutaneous/mouse lethal dose (50 percent kill): 18 mg/kgBLLIAX 38,151,1958
subcutaneous/rabbit lowest published toxic dose: 37.05 mg/kgMusculoskeletal: Other changes

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
TXCYAC 191,33,2003
subcutaneous/rat lethal dose (50 percent kill): 25.3 mg/kgImmunological Including Allergic: Decrease in cellular immune response

Immunological Including Allergic: Decrease in humoral immune response
TOVEFN -,7,2009
subcutaneous/rat lethal dose (50 percent kill): 6 mg/kgJEENAI 50,356,1957
unreported route/mammal (species unspecified) lethal dose (50 percent kill): 25 mg/kg30ZDA9 -,327,1971
unreported route/mouse lethal dose (50 percent kill): 23 mg/kgBWHOA6 44,31,1971
unreported route/rat lethal dose (50 percent kill): 10 mg/kgNYKZAU 74,41P,1978

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/rat lowest published toxic concentration: 24 µg/m3/24H/93D- continuousKidney, Ureter, and Bladder: Other changes in urine composition

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
GISAAA 33(10),10,1968
intraperitoneal/mouse lowest published toxic dose: 45 mg/kg/5D- intermittentReproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)

Reproductive: Paternal effects: Testes, epididymis, sperm duct
TOLED5 196S,S188,2010
intraperitoneal/rat lowest published toxic dose: 18.75 mg/kg/25D- intermittentEndocrine: Androgenic

Reproductive: Paternal effects: Testes, epididymis, sperm duct

Related to Chronic Data: Changes in testicular weight
JTSCDR 31,177,2006
intraperitoneal/rat lowest published toxic dose: 17.5 mg/kg/5D- intermittentReproductive: Paternal effects: Testes, epididymis, sperm ductJTSCDR 31,177,2006
intraperitoneal/rat lowest published toxic dose: 6 mg/kg/12D- intermittentReproductive: Paternal effects: Testes, epididymis, sperm ductJTSCDR 31,177,2006
intraperitoneal/rat lowest published toxic dose: 17.5 mg/kg/5D- intermittentReproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)

Reproductive: Paternal effects: Testes, epididymis, sperm duct
ETOPFR 22,315,2006
intraperitoneal/rat lowest published toxic dose: 6 mg/kg/12D- intermittentReproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)

Reproductive: Paternal effects: Testes, epididymis, sperm duct

Reproductive: Paternal effects: Prostate, seminal vesicle, Cowper's gland, accessory glands
ETOPFR 22,315,2006
intraperitoneal/rat lowest published toxic dose: 18.75 mg/kg/25D- intermittentReproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)

Reproductive: Paternal effects: Testes, epididymis, sperm duct

Related to Chronic Data: Changes in prostate weight
ETOPFR 22,315,2006
intraperitoneal/rat lowest published toxic dose: 8.75 mg/kg/5D- intermittentReproductive: Paternal effects: Testes, epididymis, sperm ductETOPFR 22,315,2006
intraperitoneal/rat lowest published toxic dose: 6 mg/kg/4D- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainJTSCDR 31,177,2006
intraperitoneal/rat lowest published toxic dose: 12 mg/kg/16D- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainJTSCDR 31,177,2006
intraperitoneal/rat lowest published toxic dose: 7 mg/kg/7D- intermittentBrain and Coverings: Other degenerative changes

Spinal Cord: Other degenerative changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
IJTHEZ 1,95,1991
intraperitoneal/rat lowest published toxic dose: 7 mg/kg/7D- intermittentBrain and Coverings: Other degenerative changes

Spinal Cord: Other degenerative changes
HBPTO* 2,1027,2001
intraperitoneal/rat lowest published toxic dose: 12 mg/kg/12D- intermittentReproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)

Reproductive: Paternal effects: Testes, epididymis, sperm duct
MUREAV 588,28,2005
intraperitoneal/rat lowest published toxic dose: 18.75 mg/kg/25D- intermittentReproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)

Reproductive: Paternal effects: Testes, epididymis, sperm duct
MUREAV 588,28,2005
oral/cat lowest published toxic dose: 91 mg/kg/26W- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gain

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
FATOAO 20(3),78,1957
oral/Dog lowest published toxic dose: 42 mg/kg/12W- continuousBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesteraseTXAPA9 1,1,1959
oral/domestic bird lowest published toxic dose: 20500 µg/kg/5D- continuousBehavioral: Food intake (animal)

Nutritional and Gross Metabolic: Weight loss or decreased weight gain

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
AECTCV 11,617,1982
oral/human lowest published toxic dose: 2.4 mg/kg/24D- intermittentBlood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
HBPTO* 1,59,2001
oral/mammal (species unspecified) lowest published toxic dose: 202 mg/kg/12D- continuousBehavioral: Food intake (animal)

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
AECTCV 16,357,1987
oral/mammal (species unspecified) lowest published toxic dose: 4450 mg/kg/30D- continuousBehavioral: Somnolence (general depressed activity)

Skin and Appendages: Other: Hair

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
NTIS** PB288-416
oral/rabbit lowest published toxic dose: 48 mg/kg/28D- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gain

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Phosphatases

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Transaminases
BECTA6 54,258,1995
oral/rabbit lowest published toxic dose: 9.2 mg/kg/57D- continuousEndocrine: Change in gonadotropins

Endocrine: Changes in spleen weight

Immunological Including Allergic: Decreased immune response
TXAPA9 32,587,1975
oral/rabbit lowest published toxic dose: 29.6 mg/kg/57D- continuousEndocrine: Other changes

Blood: Changes in spleen
TXAPA9 32,587,1975
oral/rat lowest published toxic dose: 35 mg/kg/4W- continuousLiver: Other changes

Liver: Other changes
FATOAO 39,470,1976
oral/rat lowest published toxic dose: 13200 µg/kg/6W- intermittentBehavioral: Change in motor activity (specific assay)

Gastrointestinal: Decreased motility or constipation

Kidney, Ureter, and Bladder: Incontinence
NETEEC 12,125,1990
oral/rat lowest published toxic dose: 182 mg/kg/26W- intermittentBehavioral: Alteration of classical conditioningGISAAA 23(12),19,1958
oral/rat lowest published toxic dose: 1400 µg/kg/15D- intermittentBrain and Coverings: Other degenerative changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
TXCYAC 75,13,1992
oral/rat lowest published toxic dose: 25 mg/kg/21W- intermittentBrain and Coverings: Other degenerative changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase

Nutritional and Gross Metabolic: Body temperature decrease
TXCYAC 75,13,1992
oral/rat lowest published toxic dose: 1.8 mg/kg/6D- intermittentBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesteraseTOSCF2 76,400,2003
oral/rat lowest published toxic dose: 900 mg/kg/30D- intermittentBlood: Normocytic anemia

Blood: Changes in leukocyte (WBC) count

Related to Chronic Data: Changes in testicular weight
ETOPFR 14,91,2003
oral/rat lowest published toxic dose: 4.2 mg/kg/21D- intermittentBehavioral: Alteration of classical conditioning

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
TOXID9 44,198,2005
oral/rat lowest published toxic dose: 9.9 mg/kg/11D- intermittentBrain and Coverings: Other degenerative changes

Biochemical: Metabolism (intermediary): Other proteins

Biochemical: Metabolism (intermediary): Other
TOXID9 44,199,2005
oral/rat lowest published toxic dose: 13.5 mg/kg/21D- intermittentBiochemical: Metabolism (intermediary): OtherTOXID9 44,199,2005
oral/rat lowest published toxic dose: 4.2 mg/kg/21D- intermittentBrain and Coverings: Other degenerative changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
TOXID9 78,378,2004
oral/rat lowest published toxic dose: 12 mg/kg/20D- intermittentBrain and Coverings: Other degenerative changes

Biochemical: Metabolism (intermediary): Other proteins
TOXID9 90,295,2006
oral/rat lowest published toxic dose: 2.18 mg/kg/2W- intermittentBehavioral: Alteration of classical conditioningEESADV 57,270,2004
oral/rat lowest published toxic dose: 45.5 mg/kg/13D- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainJTSCDR 31,177,2006
oral/rat lowest published toxic dose: 87.5 mg/kg/25D- intermittentReproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)

Reproductive: Paternal effects: Testes, epididymis, sperm duct

Related to Chronic Data: Changes in prostate weight
ETOPFR 22,315,2006
oral/rat lowest published toxic dose: 7.84 mg/kg/4W- intermittentKidney, Ureter, and Bladder: Changes in both tubules and glomeruli

Kidney, Ureter, and Bladder: Changes in kidney weight

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
PCBPBS 88,213,2007
oral/rat lowest published toxic dose: 22405 mg/kg/28D- continuousBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other oxidoreductases

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other transferases

Biochemical: Metabolism (intermediary): Lipids including transport
FCTOD7 46,2796,2008
oral/rat lowest published toxic dose: 12.6 mg/kg/21D- intermittentBrain and Coverings: Other degenerative changesNETEEC 31,98,2009
oral/rat lowest published toxic dose: 87.5 mg/kg/25D- intermittentEndocrine: Androgenic

Reproductive: Paternal effects: Testes, epididymis, sperm duct

Related to Chronic Data: Changes in testicular weight
JTSCDR 31,177,2006
skin/rat lowest published toxic dose: 16 mg/kg/16D- intermittentBrain and Coverings: Other degenerative changes

Blood: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
TOXID9 72,128,2003
skin/rat lowest published toxic dose: 32 mg/kg/16D- intermittentReproductive: Effects on embryo or fetus: Extra embryonic structures (e.g., placenta, umbilical cord)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
TOXID9 72,128,2003
skin/rat lowest published toxic dose: 90 mg/kg/90D- intermittentBrain and Coverings: Other degenerative changes

Biochemical: Metabolism (intermediary): Other
TOXID9 60,244,2001
skin/rat lowest published toxic dose: 65 mg/kg/13D- intermittentBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Hepatic microsomal mixed oxidase (dealkylation, hydroxylation, etc.)TOXID9 72,89,2003
skin/rat lowest published toxic dose: 9.5 mg/kg/95D- intermittentBrain and Coverings: Other degenerative changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
TOXID9 72,304,2003
skin/rat lowest published toxic dose: 60 mg/kg/30D- intermittentLiver: Hepatitis (hepatocellular necrosis), diffuse

Kidney, Ureter, and Bladder: Changes in tubules (including acute renal failure, acute tubular necrosis)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
IJEBA6 29,149,1991
subcutaneous/rat lowest published toxic dose: 20 mg/kg/10D- intermittentBehavioral: Alteration of operant conditioning

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
NETEEC 24,797,2002
subcutaneous/rat lowest published toxic dose: 21 mg/kg/7D- intermittentBrain and Coverings: Other degenerative changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
TOXID9 72,304,2003
subcutaneous/rat lowest published toxic dose: 20 mg/kg/10D- intermittentBlood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
NETEEC 24,797,2002
subcutaneous/rat lowest published toxic dose: 9 mg/kg/3D- intermittentBehavioral: Tremor

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
JTSCDR 28,427,2003
subcutaneous/rat lowest published toxic dose: 21 mg/kg/7D- intermittentBrain and Coverings: Other degenerative changesJTSCDR 28,427,2003

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 0.02 mg/m3 (inhal, vapor, skin)DTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-Not classifiable as a human carcinogenDTLVS* TLV/BEI,2013
International Agency for Research on Cancer (IARC)Cancer Review:Animal NO EVIDENCEIMSUDL 7,392,1987
International Agency for Research on Cancer (IARC)Cancer Review:Human No Adequate DataIMEMDT 30,131,1983
International Agency for Research on Cancer (IARC)Cancer Review:Group 3IMSUDL 7,56,1987
TOXICOLOGY REVIEWAQMOAC #73-19,1973
TOXICOLOGY REVIEWRREVAH 46,1,1973
TOXICOLOGY REVIEWECMAAI 14,141,1973
TOXICOLOGY REVIEWDTTIAF 80,485,1973
TOXICOLOGY REVIEWRREVAH 63,1,1976
TOXICOLOGY REVIEWMUREAV 557,109,2004
TOXICOLOGY REVIEWTOLED5 128,45,2002
TOXICOLOGY REVIEWMUREAV 567,109,2004
TOXICOLOGY REVIEWMUREAV 567,347,2004
TOXICOLOGY REVIEWMUTAEX 21,93,2006
TOXICOLOGY REVIEWMUTAEX 20,389,2005
TOXICOLOGY REVIEWCCATAR 366,1,2006
TOXICOLOGY REVIEWENTOX* -,588,2005
TOXICOLOGY REVIEWENTOX* -,85,2005
TOXICOLOGY REVIEWMUREAV 584,1,2005
TOXICOLOGY REVIEWJTEHD6 6,185,2003
TOXICOLOGY REVIEWFEREAC 73,31788,2008
TOXICOLOGY REVIEWMUREAV 543,251,2003
TOXICOLOGY REVIEWHTOPA* 1,501,2002
TOXICOLOGY REVIEWFEREAC 73,54954,2008
TOXICOLOGY REVIEWHETOEA 26,321,2007
TOXICOLOGY REVIEWFCTOD7 47,2906,2009
TOXICOLOGY REVIEWNEUCL* 23,321,2005
TOXICOLOGY REVIEWNBREV* 9,479,1985
TOXICOLOGY REVIEWTOLED5 190,107,2009
TOXICOLOGY REVIEWTXAPA9 258,309,2012
TOXICOLOGY REVIEWTOLED5 201,152,2011
TOXICOLOGY REVIEWTOLED5 209,86,2012
TOXICOLOGY REVIEWTOLED5 230,146,2014
TOXICOLOGY REVIEWTXAPA9 268,157,2013
TOXICOLOGY REVIEWMUREAV 802,1,2016
TOXICOLOGY REVIEWNETEEC 52,25,2015

Standards and Regulations

OrganizationStandardReference
Environmental Protection Agency (EPA) Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 1988 PESTICIDE SUBJECT TO REGISTRATION OR RE-REGISTRATIONFEREAC 54,7740,1989
Environmental Protection Agency (EPA) Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 1998 STATUS OF PESTICIDESSupportedRBREV* -,132,1998
Mine Safety and Health Administration (MSHA) STANDARD-airtime-weighted average 0.2 mg/m3 (skin)DTLVS* 3,168,1971
Occupational Exposure Limit IN ARGENTINA, BULGARIA, COLOMBIA, JORDAN check ACGIH TLV;
Occupational Exposure Limit IN SINGAPORE, VIETNAM check ACGIH TLV
Occupational Exposure Limit-AUSTRALIAtime-weighted average 0.2 mg/m3, JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 0.2 mg/m3;KZW 0.4 mg/m3, skin, 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 0.2 mg/m3, Skin, MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 0.2 mg/m3, skin, MAY2011
Occupational Exposure Limit-FINLANDtime-weighted average 0.2 mg/m3, short term exposure limit 0.6 mg/m3, skin, NOV2011
Occupational Exposure Limit-FRANCEVME 0.2 mg/m3, Skin, FEB2006
Occupational Exposure Limit-HUNGARYtime-weighted average 0.2 mg/m3, Skin, SEP2000
Occupational Exposure Limit-ICELANDtime-weighted average 0.2 mg/m3, skin, NOV2011
Occupational Exposure Limit-KOREAtime-weighted average 0.2 mg/m3, skin, 2006
Occupational Exposure Limit-MEXICOtime-weighted average 0.2 mg/m3;short term exposure limit 0.6 mg/m3 (skin), 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 0.2 mg/m3, skin, JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 0.2 mg/m3, JAN1999
Occupational Exposure Limit-PERUtime-weighted average 0,2 mg/m3, JUL2005
Occupational Exposure Limit-RUSSIAtime-weighted average 0.1 mg/m3, short term exposure limit 0.3 mg/m3, Skin, JUN2003
Occupational Exposure Limit-SWITZERLANDMAK-week 0.2 mg/m3, inhal, skin, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 0.2 mg/m3, Skin, 2003

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO METHYL PARATHION-air10H time-weighted average 0.2 mg/m3 (Sk)NIOSH* DHHS #92-100,1992

Status in Federal Agencies

OrganizationReference
ATSDR TOXICOLOGY PROFILE (NTIS** PB/2001/109105/AS)
EPA GENETOX PROGRAM 1988, Inconclusive: B subtilis rec assay; E coli polA without S9
EPA GENETOX PROGRAM 1988, Inconclusive: Histidine reversion-Ames test
EPA GENETOX PROGRAM 1988, Negative: Carcinogenicity-mouse/rat; In vitro UDS-human fibroblast
EPA GENETOX PROGRAM 1988, Negative: TRP reversion
EPA GENETOX PROGRAM 1988, Positive: S cerevisiae-homozygosis
EPA TSCA Section 8(d) unpublished health/safety studies
EPA TSCA TEST SUBMISSION (TSCATS) DATA BASE, JANUARY 2001
NCI Carcinogenesis Bioassay (feed);no evidence:mouse,ratNCITR* NCI-TR-157,1979
NIOSH Analytical Method, 1994: Organophosphorus pesticides, 5600
On EPA IRIS database
Page last reviewed: November 16, 2018